The present invention relates to a vehicle brake rotor and specifically to a rotor having a vented hat section in which the angles of the vents are adjusted to increase the quantity of air flowing through the vents.
Rotors are generally well known in the art, and are used extensively in caliper disc brakes, power transmission devices, clutches, and other similar machinery and mechanisms. Brake rotors are used in vehicle disc brake system which slow the vehicle by inhibiting the rotation of the vehicle wheels. Rotors typically include a central hat section secured to the spindle or axle of the vehicle wheel and a peripheral friction surface extending radially from the hat section. When the driver applies the brakes, brake pads are moved into engagement with the friction surface creating frictional forces which slow the vehicle. A vast amount of heat is generated at the friction surface by the frictional forces during braking. The heat is conducted from the friction surface to the rest of the rotor and to other components to which the rotor is connected. Excess heat leads to premature brake wear and/or failure.
Rotors are commonly cooled using moving air to absorb the heat from the rotor and carry it away. It is known to "ventilate" the rotors by forming holes or vents through portions of the rotor. As the rotor turns, air is moved through the vents to cool the rotor. The cooling effectiveness of the vents is proportional to the quantity of air passing through the vents. The more air which moves through the vents, the more heat that is dissipated and the greater the cooling effects. Therefore, it is desirable to move as much air as possible through the vents.
Vents have been formed in the hat section to move cooling air through the hat section for cooling the rotor when the rotor turns. Typically these vents have been formed through the hat wall at right angles to the hat wall surface. As the rotor turns, the right angled vents create a pressure differential from one side of the hat wall to the other which causes the air to move from the areas of high pressure to the areas of low pressure. It is desirable to increase the amount of air moved through the hat wall vents to improve the cooling effectiveness of the vents.